<div class="maxdiv">
<div class="header">
<h1>博客后台管理首页</h1>
<?php
 session_start();
if(!isset($_SESSION['username'])){
header("Location:login.php");
exit();
}else{
?>
 <a href="out.php" class="layui-btn ">退出</a> 
 <a href="" class="layui-btn ">欢迎你,管理员<?php echo $_SESSION['username']?></a>
<?php
}
?>
</div> 
</div>